tetrachord
noun
tet·ra·chord ˈte-trə-ˌkȯrd 
: a diatonic series of four tones with an interval of a perfect fourth between the first and last
Word History
Etymology
Greek tetrachordon, from neuter of tetrachordos of four strings, from tetra- + chordē string — more at yarn
First Known Use
1603, in the meaning defined above
- sub-chief
- sub-chiefs
- sub-clan
- sub-clans
- sub-cloud car
- sub-cluster
- sub-clusters
- sub-code
- sub-codes
- sub-collection
- sub-collections
- sub-college
- sub-collegiate
- sub-colonies
- sub-colony
- sub-commission
- sub-commissions
- sub-component
- sub-components
- sub-counties
- sub-county
- sub-cult
- sub-cults
- sub-cycle
- sub-dean